package com.leha.utils;

/**
 * 网络字节序的转换
 * 
 * @author dedin
 * 
 */
public class ByteConvert {
	// 以下 是整型数 和 网络字节序的 byte[] 数组之间的转换
	public static byte[] longToBytes(long n) {
		byte[] b = new byte[8];
		b[7] = (byte) (n & 0xff);
		b[6] = (byte) (n >> 8 & 0xff);
		b[5] = (byte) (n >> 16 & 0xff);
		b[4] = (byte) (n >> 24 & 0xff);
		b[3] = (byte) (n >> 32 & 0xff);
		b[2] = (byte) (n >> 40 & 0xff);
		b[1] = (byte) (n >> 48 & 0xff);
		b[0] = (byte) (n >> 56 & 0xff);
		return b;
	}

	public static void longToBytes(long n, byte[] array, int offset) {
		array[7 + offset] = (byte) (n & 0xff);
		array[6 + offset] = (byte) (n >> 8 & 0xff);
		array[5 + offset] = (byte) (n >> 16 & 0xff);
		array[4 + offset] = (byte) (n >> 24 & 0xff);
		array[3 + offset] = (byte) (n >> 32 & 0xff);
		array[2 + offset] = (byte) (n >> 40 & 0xff);
		array[1 + offset] = (byte) (n >> 48 & 0xff);
		array[0 + offset] = (byte) (n >> 56 & 0xff);
	}

	public static long bytesToLong(byte[] array) {
		return ((((long) array[0] & 0xff) << 56)
				| (((long) array[1] & 0xff) << 48)
				| (((long) array[2] & 0xff) << 40)
				| (((long) array[3] & 0xff) << 32)
				| (((long) array[4] & 0xff) << 24)
				| (((long) array[5] & 0xff) << 16)
				| (((long) array[6] & 0xff) << 8) | (((long) array[7] & 0xff) << 0));
	}

	public static long bytesToLong(byte[] array, int offset) {
		return ((((long) array[offset + 0] & 0xff) << 56)
				| (((long) array[offset + 1] & 0xff) << 48)
				| (((long) array[offset + 2] & 0xff) << 40)
				| (((long) array[offset + 3] & 0xff) << 32)
				| (((long) array[offset + 4] & 0xff) << 24)
				| (((long) array[offset + 5] & 0xff) << 16)
				| (((long) array[offset + 6] & 0xff) << 8) | (((long) array[offset + 7] & 0xff) << 0));
	}

	public static byte[] intToBytes(int n) {
		byte[] b = new byte[4];
		b[3] = (byte) (n & 0xff);
		b[2] = (byte) (n >> 8 & 0xff);
		b[1] = (byte) (n >> 16 & 0xff);
		b[0] = (byte) (n >> 24 & 0xff);
		return b;
	}

	public static void intToBytes(int n, byte[] array, int offset) {
		array[3 + offset] = (byte) (n & 0xff);
		array[2 + offset] = (byte) (n >> 8 & 0xff);
		array[1 + offset] = (byte) (n >> 16 & 0xff);
		array[offset] = (byte) (n >> 24 & 0xff);
	}

	public static int bytesToInt(byte b[]) {
		return b[3] & 0xff | (b[2] & 0xff) << 8 | (b[1] & 0xff) << 16
				| (b[0] & 0xff) << 24;
	}

	public static int bytesToInt(byte b[], int offset) {
		return b[offset + 3] & 0xff | (b[offset + 2] & 0xff) << 8
				| (b[offset + 1] & 0xff) << 16 | (b[offset] & 0xff) << 24;
	}

	public static byte[] uintToBytes(long n) {
		byte[] b = new byte[4];
		b[3] = (byte) (n & 0xff);
		b[2] = (byte) (n >> 8 & 0xff);
		b[1] = (byte) (n >> 16 & 0xff);
		b[0] = (byte) (n >> 24 & 0xff);

		return b;
	}

	public static void uintToBytes(long n, byte[] array, int offset) {
		array[3 + offset] = (byte) (n);
		array[2 + offset] = (byte) (n >> 8 & 0xff);
		array[1 + offset] = (byte) (n >> 16 & 0xff);
		array[offset] = (byte) (n >> 24 & 0xff);
	}

	public static long bytesToUint(byte[] array) {
		return ((long) (array[3] & 0xff)) | ((long) (array[2] & 0xff)) << 8
				| ((long) (array[1] & 0xff)) << 16
				| ((long) (array[0] & 0xff)) << 24;
	}

	public static long bytesToUint(byte[] array, int offset) {
		return ((long) (array[offset + 3] & 0xff))
				| ((long) (array[offset + 2] & 0xff)) << 8
				| ((long) (array[offset + 1] & 0xff)) << 16
				| ((long) (array[offset] & 0xff)) << 24;
	}

	public static byte[] shortToBytes(short n) {
		byte[] b = new byte[2];
		b[1] = (byte) (n & 0xff);
		b[0] = (byte) ((n >> 8) & 0xff);
		return b;
	}

	public static void shortToBytes(short n, byte[] array, int offset) {
		array[offset + 1] = (byte) (n & 0xff);
		array[offset] = (byte) ((n >> 8) & 0xff);
	}

	public static short bytesToShort(byte[] b) {
		return (short) (b[1] & 0xff | (b[0] & 0xff) << 8);
	}

	public static short bytesToShort(byte[] b, int offset) {
		return (short) (b[offset + 1] & 0xff | (b[offset] & 0xff) << 8);
	}

	public static byte[] ushortToBytes(int n) {
		byte[] b = new byte[2];
		b[1] = (byte) (n & 0xff);
		b[0] = (byte) ((n >> 8) & 0xff);
		return b;
	}

	public static void ushortToBytes(int n, byte[] array, int offset) {
		array[offset + 1] = (byte) (n & 0xff);
		array[offset] = (byte) ((n >> 8) & 0xff);
	}

	public static int bytesToUshort(byte b[]) {
		return b[1] & 0xff | (b[0] & 0xff) << 8;
	}

	public static int bytesToUshort(byte b[], int offset) {
		return b[offset + 1] & 0xff | (b[offset] & 0xff) << 8;
	}

	public static byte[] ubyteToBytes(int n) {
		byte[] b = new byte[1];
		b[0] = (byte) (n & 0xff);
		return b;
	}

	public static void ubyteToBytes(int n, byte[] array, int offset) {
		array[0] = (byte) (n & 0xff);
	}

	public static int bytesToUbyte(byte[] array) {
		return array[0] & 0xff;
	}

	public static int bytesToUbyte(byte[] array, int offset) {
		return array[offset] & 0xff;
	}
}
